libunwind/include/unwind_itanium.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //
   8 // C++ ABI Level 1 ABI documented at:
   9 //   https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef __ITANIUM_UNWIND_H__
  14 #define __ITANIUM_UNWIND_H__
  15
  16 struct _Unwind_Context;   // opaque
  17 struct _Unwind_Exception; // forward declaration
  18 typedef struct _Unwind_Exception _Unwind_Exception;
  19 typedef uint64_t _Unwind_Exception_Class;
  20
  21 struct _Unwind_Exception {
  22   _Unwind_Exception_Class exception_class;
  23   void (*exception_cleanup)(_Unwind_Reason_Code reason,
  24                             _Unwind_Exception *exc);
  25 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
  26   uintptr_t private_[6];
  27 #else
  28   uintptr_t private_1; // non-zero means forced unwind
  29   uintptr_t private_2; // holds sp that phase1 found for phase2 to use
  30 #endif
  31 #if __SIZEOF_POINTER__ == 4
  32   // The implementation of _Unwind_Exception uses an attribute mode on the
  33   // above fields which has the side effect of causing this whole struct to
  34   // round up to 32 bytes in size (48 with SEH). To be more explicit, we add
  35   // pad fields added for binary compatibility.
  36   uint32_t reserved[3];
  37 #endif
  38   // The Itanium ABI requires that _Unwind_Exception objects are "double-word
  39   // aligned".  GCC has interpreted this to mean "use the maximum useful
  40   // alignment for the target"; so do we.
  41 } __attribute__((__aligned__));
  42
  43 typedef _Unwind_Reason_Code (*_Unwind_Personality_Fn)(
  44     int version, _Unwind_Action actions, uint64_t exceptionClass,
  45     _Unwind_Exception *exceptionObject, struct _Unwind_Context *context);
  46
  47 #ifdef __cplusplus
  48 extern "C" {
  49 #endif
  50
  51 //
  52 // The following are the base functions documented by the C++ ABI
  53 //
  54 #ifdef __USING_SJLJ_EXCEPTIONS__
  55 extern _Unwind_Reason_Code
  56     _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object);
  57 extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object);
  58 #else
  59 extern _Unwind_Reason_Code
  60     _Unwind_RaiseException(_Unwind_Exception *exception_object);
  61 extern void _Unwind_Resume(_Unwind_Exception *exception_object);
  62 #endif
  63 extern void _Unwind_DeleteException(_Unwind_Exception *exception_object);
  64
  65
  66 extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index);
  67 extern void _Unwind_SetGR(struct _Unwind_Context *context, int index,
  68                           uintptr_t new_value);
  69 extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context);
  70 extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value);
  71
  72 #ifdef __cplusplus
  73 }
  74 #endif
  75
  76 #endif // __ITANIUM_UNWIND_H__